/*
 * Copyright (c) 2006 Intel Corporation
 * All rights reserved.
 *
 * This file is distributed under the terms in the attached INTEL-LICENSE     
 * file. If you do not find these files, copies can be found by writing to
 * Intel Research Berkeley, 2150 Shattuck Avenue, Suite 1300, Berkeley, CA, 
 * 94704.  Attention:  Intel License Inquiry.
 */

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.font.*;
import java.awt.geom.*;
import java.util.*;

/* Panel for drawing mote-data graphs */
class Graph extends JPanel
{
	final static int BORDER_LEFT = 40;
	final static int BORDER_RIGHT = 0;
	final static int BORDER_TOP = 10;
	final static int BORDER_BOTTOM = 10;

	final static int TICK_SPACING = 40;
	final static int MAX_TICKS = 16;
	final static int TICK_WIDTH = 10;

	final static int MIN_WIDTH = 50;

	int gx0, gx1, gy0, gy1; // graph bounds
	int scale = 2; // gx1 - gx0 == MIN_WIDTH << scale
	Window parent;

	/* Graph to screen coordinate conversion support */
	int height, width;
	double xscale, yscale;

	void updateConversion() {
		height = getHeight() - BORDER_TOP - BORDER_BOTTOM;
		width = getWidth() - BORDER_LEFT - BORDER_RIGHT;
		if (height < 1) {
			height = 1;
		}
		if (width < 1) {
			width = 1;
		}
		xscale = (double)width / (gx1 - gx0 + 1);
		yscale = (double)height / (gy1 - gy0 + 1);
	}

	Graphics makeClip(Graphics g) {
		return g.create(BORDER_LEFT, BORDER_TOP, width, height);
	}

	// Note that these do not include the border offset!
	int screenX(int gx) {
		return (int)(xscale * (gx - gx0) + 0.5);
	}

	int screenY(int gy) {
		return (int)(height - yscale * (gy - gy0));
	}

	int graphX(int sx) {
		return (int)(sx / xscale + gx0 + 0.5);
	}

	Graph(Window parent) {
		this.parent = parent;
		gy0 = 0; gy1 = 1000; //0xffff; // y axis range
		gx0 = 0; gx1 = MIN_WIDTH << scale;
	}

	void rightDrawString(Graphics2D g, String s, int x, int y) {
		TextLayout layout =	new TextLayout(s, parent.smallFont, g.getFontRenderContext());
		Rectangle2D bounds = layout.getBounds();
		layout.draw(g, x - (float)bounds.getWidth(), y + (float)bounds.getHeight() / 2);
	}

	protected void paintComponent(Graphics g) {
		Graphics2D g2d = (Graphics2D)g;

		/* Repaint. Synchronize on ContourTracking to avoid data changing.
		   Simply clear panel, draw Y axis and all the mote graphs. */
		synchronized (parent.parent) {
			updateConversion();
			g2d.setColor(Color.BLACK);
			g2d.fillRect(0, 0, getWidth(), getHeight());
			drawYAxis(g2d);

			Graphics clipped = makeClip(g2d);
			int count = parent.moteListModel.size();
			for (int i = 0; i < count; i++) {
				clipped.setColor(parent.moteListModel.getColor(i));
				drawGraph(clipped, parent.moteListModel.get(i));
			}
		}
	}

	/* Draw the Y-axis */
	protected void drawYAxis(Graphics2D g) {
		int axis_x = BORDER_LEFT - 1;
		int height = getHeight() - BORDER_BOTTOM - BORDER_TOP;

		g.setColor(Color.WHITE);
		g.drawLine(axis_x, BORDER_TOP, axis_x, BORDER_TOP + height - 1);

		/* Draw a reasonable set of tick marks */
		int nTicks = height / TICK_SPACING;
		if (nTicks > MAX_TICKS) {
			nTicks = MAX_TICKS;
		}

		int tickInterval = (gy1 - gy0 + 1) / nTicks;
		if (tickInterval == 0) {
			tickInterval = 1;
		}

		/* Tick interval should be of the family A * 10^B,
		   where A = 1, 2 * or 5. We tend more to rounding A up, to reduce
		   rather than increase the number of ticks. */
		int B = (int)(Math.log(tickInterval) / Math.log(10));
		int A = (int)(tickInterval / Math.pow(10, B) + 0.5);
		if (A > 2) {
			A = 5;
		} else if (A > 5) {
			A = 10;
		}

		tickInterval = A * (int)Math.pow(10, B);

		/* Ticks are printed at multiples of tickInterval */
		int tick = ((gy0 + tickInterval - 1) / tickInterval) * tickInterval;
		while (tick <= gy1) {
			int stick = screenY(tick) + BORDER_TOP;
			rightDrawString(g, "" + tick, axis_x - TICK_WIDTH / 2 - 2, stick);
			g.drawLine(axis_x - TICK_WIDTH / 2, stick,
					axis_x - TICK_WIDTH / 2 + TICK_WIDTH, stick);
			tick += tickInterval;
		}

	}

	/* Draw graph for mote nodeId */
	protected void drawGraph(Graphics g, int nodeId) {
		SingleGraph sg = new SingleGraph(g, nodeId);

		if (gx1 - gx0 >= width) {
			for (int sx = 0; sx < width; sx++)
				sg.nextPoint(g, graphX(sx), sx);
		} else {
			for (int gx = gx0; gx <= gx1; gx++)
				sg.nextPoint(g, gx, screenX(gx));
		}
	}

	/* Inner class to simplify drawing a graph. Simplify initialise it, then
	   feed it the X screen and graph coordinates, from left to right. */
	private class SingleGraph {
		int lastsx, lastsy, nodeId;

		/* Start drawing the graph mote id */
		SingleGraph(Graphics g, int id) {
			nodeId = id;
			lastsx = -1;
			lastsy = -1;
		}

		/* Next point in mote's graph is at x value gx, screen coordinate sx */
		void nextPoint(Graphics g, int gx, int sx) {
			int gy = parent.parent.data.getData(nodeId, gx);
			int sy = -1;

			if (gy >= 0) { // Ignore missing values
				double rsy = height - yscale * (gy - gy0);

				// Ignore problem values
				if (rsy >= -1e6 && rsy <= 1e6) {
					sy = (int)(rsy + 0.5);
				}

				if (lastsy >= 0 && sy >= 0) {
					g.drawLine(lastsx, lastsy, sx, sy);
				}
			}
			lastsx = sx;
			lastsy = sy;
		}
	}

	/* Update X-axis range in GUI */
	void updateXLabel() {
		parent.xLabel.setText("X: " + gx0 + " - " + gx1);
	}

	/* Ensure that graph is nicely positioned on screen. max is the largest 
	   sample number received from any mote. */
	private void recenter(int max) {
		// New data will show up at the 3/4 point
		// The 2nd term ensures that gx1 will be >= max
		int scrollby = ((gx1 - gx0) >> 2) + (max - gx1);
		gx0 += scrollby;
		gx1 += scrollby;
		if (gx0 < 0) { // don't bother showing negative sample numbers
			gx1 -= gx0;
			gx0 = 0;
		}
		updateXLabel();
	}

	/* New data received. Redraw graph, scrolling if necessary */
	void newData() {
		int max = parent.parent.data.maxX();

		if (max > gx1 || max < gx0) {
			recenter(max);
		}
		repaint();
	}

	/* User set the X-axis scale to newScale */
	void setScale(int newScale) {
		gx1 = gx0 + (MIN_WIDTH << newScale);
		scale = newScale;
		recenter(parent.parent.data.maxX());
		repaint();
	}

	/* User attempted to set Y-axis range to newy0..newy1. Refuse bogus
	   values (return false), or accept, redraw and return true. */
	boolean setYAxis(int newy0, int newy1) {
		if (newy0 >= newy1 || newy0 < 0 || newy0 > 65535 ||	newy1 < 0 || newy1 > 65535) {
			return false;
		}
		gy0 = newy0;
		gy1 = newy1;
		repaint();
		return true;
	}
}
